<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      padding: 0;
      margin: 0;
    }
    .container {
      width: 100vw;
      height: 100vh;
      background-image: url(./images/bg.png);
      background-size: cover;
    }
    .box {
      position: fixed;
      width: 1920px;
      height: 1080px;
      background: red;
      transform-origin: left top;
      left: 50%;
      top: 50%;
    }

    .top {
      width: 100px;
      height: 100px;
      background: hotpink;
      margin-left: 50px;
    }
    .bottom {
      width: 100px;
      height: 100px;
      background: blueviolet;
      margin-top: 100px;
      margin-left: 50px;
    }
  </style>
</head>
<body>
  <div class="container">
    <!-- 数据展示的区域 -->
    <div class="box">
      <div class="top">我是祖国的</div>
      <div class="bottom">老花朵</div>
    </div>
  </div>
</body>
</html>
<script>
  // 控制放大和缩小
  let box = document.querySelector('.box');
  box.style.transform = `scale(${getScale()}) translate(-50%, -50%)`

  function getScale(w=1920, h=1080) {
    // 视口宽度 /  当前宽度
    const ww = window.innerWidth / w;
    const wh = window.innerHeight / h;
    return ww > wh ? ww : wh;
  }

  window.onresize = () => {
    box.style.transform = `scale(${getScale()}) translate(-50%, -50%)`
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</script>